Antimicrobial Chemotherapy 2 Flashcards
<p>What class of drug does daptomycinbelong to?</p>
<p>Cyclic Lipopeptide</p>
<p>What is the standard length of an antimicrobial course?</p>
<p>7 days</p>
<p>What are the three ways antibiotics work?</p>
<p>Inhibition of cell wall synthesis</p>
<p>Inhibition of Protein synthesis</p>
<p>Inhibition of nucleic acid synthesis</p>
<p>How is aciclovir administered?</p>
<p>Orally or intravenously</p>
<p>Where are beta-lactamases common?</p>
<p>In Gram negative Bacilli</p>
<p>What is the activity of daptomycin?</p>
<p>Good activity against gram positive bacteria in general and MRSA in particular</p>
<p></p>
<p>(inhibition of protein synthesis)</p>
<p>What antibiotic is associated with optic nerve damage? (optic neuropathy)</p>
<p>Ethambutol</p>
<p>What are ESBL's?</p>
<p>Extended spectrum beta lactamses - they are resistant to all beta lactamases</p>
<p>What are CPE's?</p>
<p>Carbapenemase producing Enterobacteriaceae, they are extremely resistant gram negative organisms - resistant to the carpebenems. </p>
<p>What is Tenofovir used for?</p>
<p>Hepatitis B</p>
<p>What can happen to stop Beta lactams binding to PBP's?</p>
<p>Mutations in PBP genes, resulting in a modified target site, to which beta lactams will no longer bind</p>
<p>What are the susceptible groups who need extra care when administering antimicrobials?</p>
<p>Extremes of age, pregnant women, patients with renal or liver insufficiency.</p>
<p>What is the spectrum of glycopeptides?</p>
<p>They act against ONLY gram positive organisms - both aerobic and anaerobic</p>
<p>What is the difference between Nalidixic acid and Nitrofurantoin?</p>
<p>Also effective against some gram positive bacteria.</p>
<p>What is the effect of trimethoprim and sulphamethoxazole?</p>
<p>Inhibit different steps in purine synthesis</p>
<p>What drug can be used against the herpes simplex virus and the varicella zoster virus?</p>
<p>Aciclovir</p>
<p>What are the side effects of vanomycin?</p>
<p>Otoxicity, nephrotoxicity and skin rashes</p>
<p>What is the disadvantage of clindamycin?</p>
<p>Common cause of pseudomembranous collitis</p>
<p>What is defined as clinical resistance?</p>
<p>When the organism is unlikely to respond to attainable levels of that drug in the tissues</p>
<p>What is Voriconazole used to treat?</p>
<p>Aspergillosis</p>
<p>What is used to treat chronic hepatitis B and C infections?</p>
<p>Interferon - a</p>
<p>What are the signs of delayed hypersensitivity?</p>
<p>Drug rashes, drug fever, serum sickness and erythema nodosum</p>
<p>What is Nitrofurantoin active against?</p>
<p>Most gram negative organisms with the exception of pseudomonas and proteus</p>
<p>What is cystitis?</p>
<p>Lower urinary tract infections</p>
<p>What is special about the treatment of pseudomonas with ciproflaxin?</p>
<p>It is the only oral therapy available</p>
<p>How do aminoglycosides lyse most gram negative cells?</p>
<p>By inhibiting protein synthesis Staphylococci are also sensitive to aminoglycosides, streptococci are not</p>
<p>Describe the combination therapy used to treat patients with HIV</p>
<p>Combination therapy with at least three drugs.Drugs are active on at least two different stages of the HIV replication.Examples of the actions of these drugs :1. Analogue nucleoside which inhibits reverse transcriptase2. Non-nucleoside reverse transcriptase inhibitor3. Protease inhibitor which inhibits viral protease enzyme.</p>
<p>When is genotypic analysis of a virus useful?</p>
<p>May help choosing rational treatment in selected patients</p>
<p>What is the advantage of Teicoplanin?</p>
<p>Less toxic, single daily dosing advantage</p>
<p>Do all strains of C.diff produce toxins?</p>
<p>NO</p>
<p>What is metronidazole effective against?</p>
<p>It is a miscellaneous Antibiotic - effective against both gram negative and gram positive bacteriaResistance against anaerobes is virtually unknownNo useful activity against aerobes</p>
<p>What is ribavarin used for?</p>
<p>Treatment of severe respiratory syncytial virus infections.Used in combination treatment for chronic hepatitis C with Interferon - a</p>
<p>How is treatment of C.Diff achieved?</p>
<p>Metronidazole or oral vanomycin (not absorbed in the GI tract so it is the only circumstance where the oral form is used.</p>
<p>What form of penicillin has a better absorption when taken orally?</p>
<p>Phenoxymethylpenicillin,as well as amoxicillin and ampocillin (these confer better gran negative activity)</p>
<p>How is ribavarin administered?</p>
<p>Inhaled as a fine spray</p>
<p>Give an example of a oxazolidinone</p>
<p>Linezolid - protein synthesis inhibitor</p>
<p>What is the effect of zidovudine?</p>
<p>Nucleoside analogue Interferes with the action of reverse transcriptase.Slows down the replication of the virus but does not kill it. Prolongs survival of AIDS patients</p>
<p>What is a cause of diarrhoea that is associated with antibiotic therapy?</p>
<p>Diarrhoea associated with toxin production by clostridium difficile. It overgrows normal flora during therapy</p>
<p>What can cause an overgrowth in candida albicans?</p>
<p>Broad spectrum penicillins or cephalosporins causing oral and or vaginal candidiasis, also known as thrush</p>
<p>Give examples of cidal drugs</p>
<p>B lactams, aminoglycosides, glycopeptides and quinolones</p>
<p>Which drugs are usually associated with nephrotoxicity and ototoxicity?</p>
<p>Aminoglycoside (gentamicin) or with vanomycin</p>
<p>What is the main cause of CDI in recent years?</p>
<p>Use of broad spectrum antibiotics</p>
<p>Is C.diff killed by alcohol hand rub?</p>
<p>NO</p>
<p>When do patients require several weeks of antimicrobial therapy?</p>
<p>Patients with osteomyelitis, endocarditis</p>
<p>What can linezolid be used to treat?</p>
<p>MRSA</p>
<p>What is the only polyene available for intravenous polyene use?</p>
<p>Amphoterecin BTreats serious systemic fungal infectionExtremely toxicRenal, Hepatic and cardiac toxicity</p>
<p>Describe the activity of cephalosporins against gram negative and gram positive bacteria as the generation number increases</p>
<p>Gram negative activity increases - even effective against Pseudomonas Gram positive activity decreases</p>
<p>What is the most common and cheapest aminoglycoside?</p>
<p>Gentamicin</p>
<p>What is the effect of the liver on the antimicrobials?</p>
<p>Metabolised by the liver and excreted in bile</p>
<p>What is the function of Allylamines?</p>
<p>Suppress ergosterol synthesis, but act on a different stage of the synthetic pathway from Azoles.</p>
<p>What are penicillin binding proteins?</p>
<p>Enzymes responsible for peptidoglycan synthesis</p>
<p>What is the other polyene in clinical use?</p>
<p>Nystatin - available for topical use only (fungal skin infections in pessaries for vaginal candida infections) and in oral suspension (for oral and oesophageal candidiasis)</p>
<p>What determines the choice between Vanomycin and teicoplanin?</p>
<p>The two glycopeptides have the same spectrum of activity, the choice is however dependant on cost </p>
<p>What drugs are associated with hepatotoxicity?</p>
<p>Tetracyline, isoniazid and rifampicin (anti tuberculosis drugs), flucloxacilin</p>
<p>What are examples of Echinocandins?</p>
<p>Caspofungin, Mycafungin and anidulafungin</p>
<p>Describe the problems associated with Fluconazole and resistance</p>
<p>Resistance among some candida species is emergingMajority of Candida albicans (commonest species of yeast associated clinical infection) with strains remain sensitive but resistance can emerge during treatment, </p>
<p>Why has cephalosporin use decreased over recent years?</p>
<p>They appear to encourage clostridium difficile infections</p>
<p>What drugs are both licensed for the treatment of influenza and what are there limitations?</p>
<p>Zanamavir and Oseltamavir Used to treat A or B within 48 hours of symptoms and also for post-exposure prophylaxis.</p>
<p>Describe the resistance of bacteria with modified PBP's against beta lactams</p>
<p>Resistant to all beta lactam agents</p>
<p>Describe the action of fluconazole</p>
<p>Used for oral and parenteral treatment of yeast infections (no activity against filamentous fungi-aspergillus)</p>
<p>What is the first choice treatment against staphylococcal infections (which are gram positive btw)? And Why?</p>
<p>Flucloxacillin - resistant to the actions of staphylococcal beta lactamase.</p>
<p>What can linezolid cause?</p>
<p>Bone marrow suppression</p>
<p>What are the different forms of fungi?</p>
<p>Yeasts and filamentous fungi (moulds)</p>